Loans and Allowance for Credit Losses - Changes in allowance (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Changes in the allowance
Beginning balance	$ 35,102	$ 31,713	$ 31,146	$ 31,572
Provision for credit losses	191		460
Loan charge-offs	(108)	(674)	(365)	(719)
Loan recoveries	511	334	598	520
Ending balance	35,696	31,373	35,696	31,373
Provision for off-balance sheet credit loss	186		44
Debt securities held-to-maturity credit loss	5		46
Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			3,857
Unallocated
Changes in the allowance
Beginning balance	901	457	268	1,180
Provision for credit losses	826	595	743	(128)
Ending balance	1,727	1,052	1,727	1,052
Unallocated \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			716
Commercial
Changes in the allowance
Beginning balance	24,550	22,551	23,292	22,084
Provision for credit losses	(491)	30	(357)	387
Loan charge-offs	(85)	(637)	(260)	(664)
Loan recoveries	450	101	517	238
Ending balance	24,424	22,045	24,424	22,045
Commercial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			1,232
Commercial \| Commercial and industrial
Changes in the allowance
Beginning balance	7,800	9,795	9,158	8,925
Provision for credit losses	(340)	1,085	(717)	1,856
Loan charge-offs	(85)	(637)	(260)	(664)
Loan recoveries	438	90	494	216
Ending balance	7,813	10,333	7,813	10,333
Commercial \| Commercial and industrial \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			(862)
Commercial \| Real estate construction
Changes in the allowance
Beginning balance	4,406	810	1,446	783
Provision for credit losses	(760)	68	(318)	95
Ending balance	3,646	878	3,646	878
Commercial \| Real estate construction \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			2,518
Commercial \| Commercial real estate
Changes in the allowance
Beginning balance	12,344	11,946	12,688	12,376
Provision for credit losses	609	(1,123)	678	(1,564)
Loan recoveries	12	11	23	22
Ending balance	12,965	10,834	12,965	10,834
Commercial \| Commercial real estate \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			(424)
Consumer
Changes in the allowance
Beginning balance	9,651	8,705	7,586	8,308
Provision for credit losses	(144)	(625)	74	(259)
Loan charge-offs	(23)	(37)	(105)	(55)
Loan recoveries	61	233	81	282
Ending balance	9,545	8,276	9,545	8,276
Consumer \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			1,909
Consumer \| Real estate junior lien
Changes in the allowance
Loan charge-offs			(77)
Consumer \| Residential \| Real estate first mortgage
Changes in the allowance
Beginning balance	8,060	6,661	5,769	6,532
Provision for credit losses	(159)	(486)	50	(357)
Loan recoveries			2
Ending balance	7,901	6,175	7,901	6,175
Consumer \| Residential \| Real estate first mortgage \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			2,080
Consumer \| Residential \| Real estate junior lien
Changes in the allowance
Beginning balance	1,277	1,400	1,289	1,295
Provision for credit losses	28	(134)	154	(42)
Loan charge-offs			(77)
Loan recoveries	46	201	52	214
Ending balance	1,351	1,467	1,351	1,467
Consumer \| Residential \| Real estate junior lien \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			(67)
Consumer \| Other revolving and installment
Changes in the allowance
Beginning balance	314	644	528	481
Provision for credit losses	(13)	(5)	(130)	140
Loan charge-offs	(23)	(37)	(28)	(55)
Loan recoveries	15	32	27	68
Ending balance	$ 293	$ 634	293	$ 634
Consumer \| Other revolving and installment \| Adoption of CECL \| Cumulative Effect, Period of Adoption, Adjustment
Changes in the allowance
Beginning balance			$ (104)

Amount of increase in allowance for credit loss on accounts receivable, from recovery.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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